package com.lijing.BinaryTree;

import java.security.PublicKey;
import java.sql.PreparedStatement;
import java.util.function.BinaryOperator;

public class BinaryTreeDemo {
    public static void main(String[] args) {
        BinaryTree binaryTree = new BinaryTree();
        HeroNode root = new HeroNode(1,"宋江");
        HeroNode node1 = new HeroNode(2,"吴用");
        HeroNode node2 = new HeroNode(3,"卢俊义");
        HeroNode node3 = new HeroNode(4,"林冲");
        HeroNode node4 = new HeroNode(5,"关胜");

        root.setLeft(node1);
        root.setRight(node2);
        node2.setRight(node3);
        node2.setLeft(node4);


        binaryTree.setRoot(root);

        System.out.println("删除前的二叉树为：");
        binaryTree.preOrder();
        binaryTree.delNode(3);
        System.out.println("删除后的二叉树为：");
        binaryTree.preOrder();
//        System.out.println("前序遍历：");//12354
//        binaryTree.preOrder();
//        System.out.println("中序遍历：");//21534
//        binaryTree.infixOrder();
//        System.out.println("后序遍历：");//25431
//        binaryTree.postOrder();



    }
}

class BinaryTree{
    private HeroNode root;

    public BinaryTree() {
    }

    public BinaryTree(HeroNode root) {
        this.root = root;
    }

    public HeroNode getRoot() {
        return root;
    }

    public void setRoot(HeroNode root) {
        this.root = root;
    }

    public void preOrder(){
        if (this.root != null) {
            this.root.preOrder();
        }else {
            System.out.println("二叉树为空，无法前序遍历！");
        }
    }
    public void infixOrder(){
        if (this.root != null) {
            this.root.infixOrder();
        }else {
            System.out.println("二叉树为空，无法中序遍历！");
        }
    }
    public void postOrder(){
        if (this.root != null) {
            this.root.postOrder();
        }else {
            System.out.println("二叉树为空，无法后序遍历！");
        }
    }

    public HeroNode preFindByNo(int no){
        if (this.root != null) {
            return this.root.preFindByNo(no);
        }else {
            System.out.println("二叉树为空，无法查找！");
            return null;
        }
    }
    public HeroNode infixFindByNo(int no){
        if (this.root != null) {
            return this.root.infixFindByNo(no);
        }else {
            System.out.println("二叉树为空，无法查找！");
            return null;
        }
    }
    public HeroNode postFindByNo(int no){
        if (this.root != null) {
            return this.root.postFindByNo(no);
        }else {
            System.out.println("二叉树为空，无法查找！");
            return null;
        }
    }

    public void delNode(int no){
        if (root != null){
            if (root.getNo() == no){
                root = null;
            }else {
                root.delNode(no);
            }

        }else {
            System.out.println("空树无法删除！");
        }
    }
}


class HeroNode{
    private int no;
    private String name;
    private HeroNode left;
    private HeroNode right;

    public HeroNode(int no, String name) {
        this.no = no;
        this.name = name;
    }

    public int getNo() {
        return no;
    }

    public void setNo(int no) {
        this.no = no;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public HeroNode getLeft() {
        return left;
    }

    public void setLeft(HeroNode left) {
        this.left = left;
    }

    public HeroNode getRight() {
        return right;
    }

    public void setRight(HeroNode right) {
        this.right = right;
    }

    @Override
    public String toString() {
        return "HeroNode{" +
                "no=" + no +
                ", name='" + name + '\'' +
                '}';
    }

    //前序遍历
    public void preOrder(){
        //先输出父节点
        System.out.println(this);
        //递归向左子树前序遍历
        if(this.left != null){
            this.left.preOrder();
        }
        //递归向右子树前序遍历
        if(this.right != null){
            this.right.preOrder();
        }

    }

    //中序遍历
    public void infixOrder() {
        //递归向左子树中序遍历
        if (this.left != null) {
            this.left.infixOrder();
        }
        //输出父节点
        System.out.println(this);
        //递归向右子树中序遍历
        if (this.right != null) {
            this.right.infixOrder();
        }
    }

    //后序遍历
    public void postOrder(){
        if(this.left != null){
            this.left.postOrder();
        }
        if(this.right != null){
            this.right.postOrder();
        }
        System.out.println(this);
    }

    //前序查找
    public HeroNode preFindByNo(int no){
        //如果当前节点no是否等于要查找的，如果是则返回当前节点
        //如果不相等，判断左子节点是否为空，非空则递归前序查找，找到则返回
        //如果左递归未找到则右递归前序查找
        System.out.println("进入一次前序遍历！");
        if(this.no == no){
            return this;
        }
        HeroNode resNode = null;
        if(this.left != null){
            resNode =  this.left.preFindByNo(no);
        }
        //如果找到就返回
        if(resNode != null){
            return resNode;
        }

        if(this.right != null){
            resNode = this.right.preFindByNo(no);
        }
        return resNode;
    }

    //中序查找
    public HeroNode infixFindByNo(int no){
        HeroNode resNode = null;
        if(this.left != null){
            resNode = this.left.infixFindByNo(no);
        }
        if(resNode != null){
            return resNode;
        }
        System.out.println("进入一次中序遍历");
        if(this.no == no){
            return this;
        }
        if(this.right != null){
            resNode = this.right.infixFindByNo(no);
        }
        return resNode;
    }

    //后序查找
    public HeroNode postFindByNo(int no){

        HeroNode resNode = null;
        if(this.left != null){
            resNode = this.left.postFindByNo(no);
        }
        if(resNode != null){
            return resNode;
        }
        if(this.right != null){
            resNode = this.right.postFindByNo(no);
        }
        if(resNode != null){
            return resNode;
        }
        System.out.println("进入一次后序遍历");
        if (this.no == no){
            return this;
        }
        return null;
    }

    //删除节点，叶子节点直接删除节点，非叶子节点直接删除子树
    public void delNode(int no){
        if (this.left != null && this.left.no == no){
            this.left = null;
            return;
        }
        if (this.right != null && this.right.no == no){
            this.right = null;
            return;
        }
        //未删除成功就递归
        if (this.left != null){
            this.left.delNode(no);
        }
        if (this.right != null){
            this.right.delNode(no);
        }
    }
}